Which of These Statements About Carbohydrates Is Correct

Which of these statements about carbohydrates is correct ?

A) Carbohydrates contain both a carboxyl and an amine group.
B) Carbohydrates contain a phosphate backbone with sugar groups.
C) Carbohydrates release more energy per gram than any other biomolecule.
D) Carbohydrates are polyhydroxy aldehydes and ketones or their derivatives.
E) Carbohydrates are formed when a carboxylic acid reacts with glycerol in an acidic environment.